Title :
A novel method for forming gate spacer and its effects on the W/WNx/poly-Si gate stack
Author :
Kim, Yong Soo ; Lim, Kwan-Yong ; Oh, Jae-Geun ; Jang, Se-Aug ; Cho, Heung-Jae ; Yang, Jun-Mo ; Suh, Jai-Bum ; Chung, Su-Ock ; Park, Soo-Young ; Yang, Hong-Seon ; Sohn, Hyun-Chul ; Kim, Jin-Woong
Author_Institution :
Memory R&D Div., Hynix Semicond. Inc., Kyoungki-do, South Korea
Abstract :
A novel method for forming the SiO2/Si3N4 (O/N) gate spacer has been developed through applying a low temperature atomic layer deposition (ALD) SiO2 film. Using this scheme, the Si-O rich interfacial dielectric layer formation and the metal (W) contamination caused by the selective oxidation (SO) process were controlled. Our technique also suppresses the thickness increase of the gate oxide during the SO and enhances the rounding of gate bird´s beak (GBB) at the gate edges. Furthermore, the O/N gate spacered device exhibits less junction leakage currents, about 1 order of magnitude lower gate induced drain leakage (GIDL) currents at the same Vt, and better hot carrier degradation (HCD) immunity compared to the N/O/N gated spacer device.
Keywords :
atomic layer deposition; dielectric thin films; hot carriers; leakage currents; oxidation; silicon compounds; tungsten; tungsten compounds; GIDL current; Si-O rich interfacial dielectric layer formation; SiO2-Si3N4-W-WN-Si; atomic layer deposition; gate bird beak rounding; gate induced drain leakage; gate oxide thickness; gate spacer formation; gate stack; hot carrier degradation immunity; junction leakage currents; low temperature ALD; metal contamination; selective oxidation process; Atomic layer deposition; Contamination; Degradation; Dielectrics; Hot carriers; Leakage current; Oxidation; Process control; Semiconductor films; Temperature;
Conference_Titel :
Solid-State Device Research conference, 2004. ESSDERC 2004. Proceeding of the 34th European
Print_ISBN :
0-7803-8478-4
DOI :
10.1109/ESSDER.2004.1356497
